118A>G and IVS2+691G>C polymorphisms of OPRM1 gene have no influence on cold-pain sensitivity among healthy opioid-naive malay males
Document Type
Article
Publication Date
1-1-2016
Abstract
Objective: Common polymorphisms of the mu-type opioid receptor (OPRM1) including 118A > G and IVS2+691G > C may affect experimental pain responses in healthy subjects, and the effect could be ethnic-dependent. The aim of this study was to investigate the influence of these OPRM1 polymorphisms on cold-pressor pain responses among healthy opioid-naive Malay males. Methods: Pain-threshold, pain-tolerance, and pain-intensity in response to the cold pressor test (CPT) were measured in healthy opioid-naive Malay males. DNA was extracted from the collected venous blood before PCR-genotyping. Repeated measure analysis of variance (RM-ANOVA) was used to compare CPT responses and OPRM1 polymorphisms (118A>G and IVS2+691G>C) according to their genotypes and allelic additive models, genotype dominant and recessive models, haplotypes, and diplotypes. Results: A total of 152 participants were recruited. Both 118A>G and IVS2+691G>C polymorphisms were not associated with cold-pressor pain-threshold, pain-tolerance and pain-intensity despite using genotypes and allelic additive models and genotype dominant and recessive models (all p>0.05). Likewise, there were no significant associations between haplotypes and diplotypes for the 118A>G and IVS2+691G>C polymorphisms and the three cold-pain responses (all p>0.05). Conclusion: The common OPRM1 polymorphisms (i.e., 118A>G and IVS2+691G>C), are not associated with cold-pressor pain responses in healthy opioid-naive Malay males. However, this may be unique for this particular ethnicity. Other polymorphisms may be more relevant for this population, and this should be further investigated.
Keywords
Cold pressor test (CPT), Malays, Male, Mu 1 gene (OPRM1), Mu-type opioid receptor (OPRM1), Opioid receptor, Opioid-naive, Pain-intensity, Pain-threshold, Pain-tolerance
Divisions
fac_med
Publication Title
International Journal of Pharmacy and Pharmaceutical Sciences
Volume
8
Issue
7
Publisher
Innovare Academics Sciences Pvt. Ltd